systemd-timesyncd inactive after migration from chrony

📖 ~1 min read

Table of contents

1. Symptom & Impact
2. Environment & Reproduction
3. Root Cause Analysis
4. Quick Triage
5. Step-by-Step Diagnosis
6. Solution – Primary Fix
7. Solution – Alternative Approaches
8. Verification & Acceptance Criteria
9. Rollback Plan
10. Prevention & Hardening
11. Related Errors & Cross-Refs
12. References & Further Reading

Symptom & Impact

Time synchronization is disabled after replacing chrony with systemd-timesyncd.

Environment & Reproduction

timedatectl shows System clock synchronized: no and NTP service inactive.

Root Cause Analysis

Inspect systemctl status systemd-timesyncd, verify conflicting NTP daemons, and check resolved DNS for NTP hosts.

Quick Triage

timesyncd is masked or blocked by leftover chrony configuration and disabled service state.

Step-by-Step Diagnosis

Unmask and enable systemd-timesyncd, remove conflicting daemons, and define reachable NTP servers.

Solution – Primary Fix

Confirm timedatectl reports synchronization and observe stable offset over several minutes.

Solution – Alternative Approaches

Use one approved time synchronization stack per host class to avoid service conflicts.

Verification & Acceptance Criteria

Reinstall and re-enable chrony if timesyncd is unsuitable for your environment requirements.

Rollback Plan

Enforce NTP daemon choice with compliance checks during provisioning and drift remediation.

Prevention & Hardening

timedatectl; systemctl unmask systemd-timesyncd; systemctl enable –now systemd-timesyncd

Related Errors & Cross-Refs

Attach service unit status, masking state, and network path to NTP peers.

Related tutorial: View the step-by-step tutorial for Ubuntu 26.04 LTS.

View all Ubuntu 26.04 LTS tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

Virtualized hosts with unstable hypervisor clocks may still require chrony for better drift handling.